CVE-2025-69906
📋 TL;DR
Monstra CMS v3.0.4 contains an arbitrary file upload vulnerability in the Files Manager plugin that allows attackers to upload malicious files to web-accessible directories. This bypasses blacklist-based file extension validation and can lead to remote code execution. All users running Monstra CMS v3.0.4 with the Files Manager plugin enabled are affected.
💻 Affected Systems
- Monstra CMS
📦 What is this software?
Monstra Cms by Monstra
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise through remote code execution, allowing attackers to execute arbitrary commands, steal data, install malware, or pivot to other systems.
Likely Case
Webshell deployment leading to data theft, defacement, or use as a foothold for further attacks within the network.
If Mitigated
File uploads blocked or sanitized, preventing code execution but potentially allowing denial of service through storage exhaustion.
🎯 Exploit Status
Exploitation requires access to the Files Manager interface, which typically requires authentication. Public proof-of-concept code is available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if available or implementing workarounds.
🔧 Temporary Workarounds
Disable Files Manager Plugin
linuxRemove or disable the vulnerable Files Manager plugin to prevent file uploads.
mv plugins/box/filesmanager plugins/box/filesmanager.disabled
Implement Web Server Restrictions
allConfigure web server to block execution of uploaded files in upload directories.
# Apache: Add to .htaccess in upload directory
<FilesMatch "\.(php|phtml|php3|php4|php5|php7|phps|php8|inc|pl|py|jsp|asp|aspx|cgi|sh)">
Order Deny,Allow
Deny from all
</FilesMatch>
# Nginx: Add to server block
location ~* \.(php|phtml|php3|php4|php5|php7|phps|php8|inc|pl|py|jsp|asp|aspx|cgi|sh)$ {
deny all;
}
🧯 If You Can't Patch
- Disable file upload functionality entirely in Monstra CMS configuration.
- Implement strict file upload validation with whitelist-based extension checking and content-type verification.
🔍 How to Verify
Check if Vulnerable:
Check if Monstra CMS version is 3.0.4 and Files Manager plugin is enabled in plugins/box/filesmanager directory.Check Version:
cat monstra/version.txtVerify Fix Applied:
Verify Files Manager plugin is disabled or removed, and test file upload functionality with malicious extensions.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads with executable extensions (php, jsp, asp, etc.)
- Multiple failed upload attempts followed by successful upload
- Web server logs showing execution of files from upload directories
Network Indicators:
- HTTP POST requests to upload endpoints with executable file content
- Subsequent requests to uploaded files in upload directories
SIEM Query:
source="web_server_logs" AND (uri="/admin/index.php?id=filesmanager" OR uri MATCHES "\.(php|jsp|asp)") AND method="POST"